This invention relates to an intraventricular expansible assist pump for use as circulatory support in patients with a severe ventricular cardiac shock.
This very serious complication can be developed under the following circumstances:
(a) In patients with acute myocardial infarction in a state of cardiogenic shock. In the United States over a million and a half acute myocardial infarctions are reported every year, of which about 60,000 develop cardiogenic shock.
(b) In patients who, after an open heart operation, cannot be weaned off the extracorporeal circulation on account of myocardial failure and low cardiac output. Every year over 200,000 operations with extracorporeal circulation are carried out all over the world. Approximately in 7% of the cases (some 15,000 patients per year) it is not possible to wean the patient off the extracorporeal circulation. Half of these cases can be solved with an IABP (Intra-aortic counterpulsation) system and inotropic drugs, but the other half requires a more efficient mechanical circulation support.
(c) As a bridge to heart transplants. The scarcity of donors and the long Waiting lists make it every day more necessary to have an available system to sustain the life of the waiting recipient.
(d) Severe chronic cardiomyopathies in a situation of low cardiac output. Estimated in over 25,000 cases per year.
(e) Accidents in hemodynamic labs, especially in cases when angioplasties are done in critical cases.
Nowadays there exist several systems of mechanical circulatory assistance, some available without restrictions and others still in the clinical research stage.
The main characteristics of the most important ones are recorded hereafter for the purpose of establishing comparisons with the pump of the invention.